Macaroni and Cheese - prepared, uncooked in the fridge for 5 days OK?

I will be out of town until right before the Christmas holiday and will not return until the morning of dinner. Ideally, I would love to prepare most of the dishes ahead of time and reheat/cook quickly the day of. Would it be OK to make the macaroni and cheese ahead (custard style with a pretty high moisture sauce) and stash in the coldest part of the fridge for a 5 days or so and then bake?

my understanding is that raw, cracked eggs last about 2-4 days in the fridge. So you're on the outside of that window.

I'm not sure exactly how you're preparing your mac and cheese ahead of time and I think that will impact how long they will keep as well. If you are cooking the sauce before mixing with the macaroni you might be okay. If you are just warming them then you run the risk of creating a very nice warm incubation environment, causing issues.